rocksdb/examples/rocksdb_option_file_example.ini
Marton Trencseni 522de4f59e Adding pin_l0_filter_and_index_blocks_in_cache feature.
Summary:
When a block based table file is opened, if prefetch_index_and_filter is true, it will prefetch the index and filter blocks, putting them into the block cache.
What this feature adds: when a L0 block based table file is opened, if pin_l0_filter_and_index_blocks_in_cache is true in the options (and prefetch_index_and_filter is true), then the filter and index blocks aren't released back to the block cache at the end of BlockBasedTableReader::Open(). Instead the table reader takes ownership of them, hence pinning them, ie. the LRU cache will never push them out. Meanwhile in the table reader, further accesses will not hit the block cache, thus avoiding lock contention.
When the table reader is destroyed, it releases the pinned blocks (if there were any). This has to happen before the cache is destroyed, so I had to introduce a TableReader::Close(), to guarantee the order of destruction.

Test Plan:
Added two unit tests for this. Existing unit tests run fine (default is pin_l0_filter_and_index_blocks_in_cache=false).

DISABLE_JEMALLOC=1 OPT=-g make all valgrind_check -j32
  Mac: OK.
  Linux: with D55287 patched in it's OK.

Reviewers: sdong

Reviewed By: sdong

Subscribers: andrewkr, leveldb, dhruba

Differential Revision: https://reviews.facebook.net/D54801
2016-03-17 22:40:01 +00:00

145 lines
4.5 KiB
INI

# This is a RocksDB option file.
#
# A typical RocksDB options file has four sections, which are
# Version section, DBOptions section, at least one CFOptions
# section, and one TableOptions section for each column family.
# The RocksDB options file in general follows the basic INI
# file format with the following extensions / modifications:
#
# * Escaped characters
# We escaped the following characters:
# - \n -- line feed - new line
# - \r -- carriage return
# - \\ -- backslash \
# - \: -- colon symbol :
# - \# -- hash tag #
# * Comments
# We support # style comments. Comments can appear at the ending
# part of a line.
# * Statements
# A statement is of the form option_name = value.
# Each statement contains a '=', where extra white-spaces
# are supported. However, we don't support multi-lined statement.
# Furthermore, each line can only contain at most one statement.
# * Sections
# Sections are of the form [SecitonTitle "SectionArgument"],
# where section argument is optional.
# * List
# We use colon-separated string to represent a list.
# For instance, n1:n2:n3:n4 is a list containing four values.
#
# Below is an example of a RocksDB options file:
[Version]
rocksdb_version=4.3.0
options_file_version=1.1
[DBOptions]
stats_dump_period_sec=600
max_manifest_file_size=18446744073709551615
bytes_per_sync=8388608
delayed_write_rate=2097152
WAL_ttl_seconds=0
WAL_size_limit_MB=0
max_subcompactions=1
wal_dir=
wal_bytes_per_sync=0
db_write_buffer_size=0
keep_log_file_num=1000
table_cache_numshardbits=4
max_file_opening_threads=1
writable_file_max_buffer_size=1048576
random_access_max_buffer_size=1048576
use_fsync=false
max_total_wal_size=0
max_open_files=-1
skip_stats_update_on_db_open=false
max_background_compactions=16
manifest_preallocation_size=4194304
max_background_flushes=7
is_fd_close_on_exec=true
max_log_file_size=0
advise_random_on_open=true
create_missing_column_families=false
paranoid_checks=true
delete_obsolete_files_period_micros=21600000000
disable_data_sync=false
log_file_time_to_roll=0
compaction_readahead_size=0
create_if_missing=false
use_adaptive_mutex=false
enable_thread_tracking=false
disableDataSync=false
allow_fallocate=true
error_if_exists=false
recycle_log_file_num=0
skip_log_error_on_recovery=false
allow_mmap_reads=false
allow_os_buffer=true
db_log_dir=
new_table_reader_for_compaction_inputs=true
allow_mmap_writes=false
[CFOptions "default"]
compaction_style=kCompactionStyleLevel
compaction_filter=nullptr
num_levels=6
table_factory=BlockBasedTable
comparator=leveldb.BytewiseComparator
max_sequential_skip_in_iterations=8
soft_rate_limit=0.000000
max_bytes_for_level_base=1073741824
memtable_prefix_bloom_probes=6
memtable_prefix_bloom_bits=0
memtable_prefix_bloom_huge_page_tlb_size=0
max_successive_merges=0
arena_block_size=16777216
min_write_buffer_number_to_merge=1
target_file_size_multiplier=1
source_compaction_factor=1
max_bytes_for_level_multiplier=8
compaction_filter_factory=nullptr
max_write_buffer_number=8
level0_stop_writes_trigger=20
compression=kSnappyCompression
level0_file_num_compaction_trigger=4
purge_redundant_kvs_while_flush=true
max_write_buffer_number_to_maintain=0
memtable_factory=SkipListFactory
max_grandparent_overlap_factor=8
expanded_compaction_factor=25
hard_pending_compaction_bytes_limit=137438953472
inplace_update_num_locks=10000
level_compaction_dynamic_level_bytes=true
level0_slowdown_writes_trigger=12
filter_deletes=false
verify_checksums_in_compaction=true
min_partial_merge_operands=2
paranoid_file_checks=false
target_file_size_base=134217728
optimize_filters_for_hits=false
merge_operator=PutOperator
compression_per_level=kNoCompression:kNoCompression:kNoCompression:kSnappyCompression:kSnappyCompression:kSnappyCompression
compaction_measure_io_stats=false
prefix_extractor=nullptr
bloom_locality=0
write_buffer_size=134217728
disable_auto_compactions=false
inplace_update_support=false
[TableOptions/BlockBasedTable "default"]
format_version=2
whole_key_filtering=true
skip_table_builder_flush=false
no_block_cache=false
checksum=kCRC32c
filter_policy=rocksdb.BuiltinBloomFilter
block_size_deviation=10
block_size=8192
block_restart_interval=16
cache_index_and_filter_blocks=false
pin_l0_filter_and_index_blocks_in_cache=false
index_type=kBinarySearch
hash_index_allow_collision=true
flush_block_policy_factory=FlushBlockBySizePolicyFactory